The Internet has changed society and is as much a part of modern culture as television and telephones. People are becoming increasingly connected to share and access information. This interconnectivity promotes improvements in the computing and communication infrastructure.
Much of this infrastructure was designed for entertainment or communication, but is being adapted to deliver general data. The addition of general information and data transmission over the legacy infrastructure has necessarily been somewhat restrained by the need for the infrastructure to continue its initial functions. Furthermore, legacy technical characteristics of this infrastructure influence the various solutions to include information storage and transmission. Most major entertainment and communication channels now include computer networking capabilities.
Many people get their television service through cable television (CATV). CATV was initially developed to deliver television signals to areas where antennas had difficulty picking up television broadcasts. Coaxial cabling is the primary type of cabling used by the cable television industry because it is much less susceptible to interference and can carry large amounts of data.
An example use of data over a cable television network was approved by the International Telecommunications Union (ITU) which includes interface requirements for high speed data communication, and is called the data over cable service interface specification (DOCSIS).
According to DOCSIS, placing upstream and downstream data onto the cable television network requires special equipment. On the customer end, a cable modulator/demodulator (Cable Modem, or CM) transmits and receives data over the cable television infrastructure and on the cable provider end a Cable Modem Termination System (CMTS) is used to place and retrieve data from the cable television network. The CM then provides cable network access to a multitude of Customer Premise Equipment (CPE) devices.
Historically, the CPE devices sent data according to Internet Protocol version 4 (IPv4) through a CM and a CMTS to communicate with the Internet. Recently Internet Protocol version 6 (IPv6) became available and offers several advantages over IPv4. One advantage is the increased address space offered by IPv6, which is necessary for the deployment of large cable networks. Another advantage is the ability for a device to determine its own IPv6 address through StateLess Address AutoConfiguration (SLAAC). Accordingly, for this and other reasons, there is a need to adapt cable networks to use IPv6 communications.
Regardless of whether IPv4 or IPv6 is used, the CMTS needs to configure associated CMs and CPE devices. IPv4 provides stateful provisioning methods to configure CMs and CPE devices. Under stateful provisioning, the CMTS assigns addresses based on stored and predefined profiles for the CM and CPE devices.
In contrast, IPv6 provides the option to use both stateful provisioning and SLAAC. SLAAC generally requires less management by the CMTS. For example, the aforementioned profile for each CM and CPE device is not used by a CMTS under SLAAC. SLAAC also does not require the CMTS to maintain state for the provisioned devices. Accordingly, SLAAC generally scales better when a CMTS has to configure a large number of CM and CPE devices. SLAAC is therefore preferred.
Under SLAAC, instead of assigning the full address to the CM and CPE device based on individual stored profiles, a CMTS provides only the IPv6 prefix being utilized on the link. The devices then prepend the IPv6 prefix to their own unique identifiers to configure the full IPv6 address.
The lack of the profile in the CMTS makes it difficult to determine whether a particular address belongs to a CM or CPE device. This can be problematic for Multiple-System Operators (MSOs) because, for management and security reasons, they need an easy way to determine whether an address belongs to CM devices they manage or to CPE devices they do not manage.
Because of the forgoing limitations SLAAC of CMs and CPE can be impractical despite its benefits. The disclosure that follows solves this and other problems.